s salisbury



(No Model.) 2 Sheets-Sheet 1.

E. E. SALISBURY & A. E. DEAN. CALL BOX SYSTEM.

No. 605,345. Patented June 7, 1898.

A TTOHNE YS.

(No Model.) 2 SheetsS heet 2.

E... B. SALISBURY & A. E. DEAN.

GALL BOX SYSTEM.

No. 605,345. Patented June 7, 1898 WITNESSES iltnrnn 3 Starts rarest rrrcn. I

EDGAR E. SALISBURY AND ALBERT E. DEAN, OF TACOMA, VVASIIINGTON ASSIGNORS TO THEMSELVES AND FRANK B. TAYLOR, OF SAME PLACE.

CALL-BOX SYSTEM.

SPECIFICATION forming part of Letters Patent No. 605,345, dated June 7, 1 898. A Application filed June 22, 1897. Serial No. 641,773. (No model.)

T on whom it may concern:

Be it known that we, EDGAR E. SALISBURY and ALBERT E. DEAN, of Tacoma, in the county of Pierce and State of Washington, have invented a new and Improved Messenger-Call-Box System, of which the following is a full, clear, and exact description.

This invention relates particularly to callbox systems in which the telephone forms an important part and also to the method of operating an electric or magnetic speakingtransmitter from a'point to or from the central office over a permanently-magnetized circuit without the use of a local battery to operate the same and to a system of wiring the central oflice which will also obviate the use of a local battery on the telephone; and the object is to out the primary circuit of a coil Within which the transmitter is located in and out of the mainline circuit when either in use or not in use, as the case may be, withoutdisturbing the secondary, which is the local circuit-,in this case independent from the main line, and within which is located the hand-tele ondary part of the coil is out in and out of the] main circuit when in use or not in use, as will hereinafter appear. I

Another object is to providea simple means of signaling the central office when hanging up the receiver,to indicate that the subscriber is through with the conversation, and also to enable the subscriber to carry on conversation with the central office by operating push-buttons to close a circuit through a ground-line when the main wires are short-circuited or broken.

We will describe the telephone system embodyin g our invention, and then point out the novel features in the appended claims.

Reference-is tobe had to the accompanying drawings, forming a part of this specification, inwhich similarcharacters of reference indicate corresponding parts in all the figures.

Figure 1 is a diagrammatic view of the telephone part of the central ofiice wiring system.

Fig 2 is a detail showing the circuit-closing plugas connected with contact-points, and

Fig. 3 is a diagrammatic view showing the wiring in the call-box.

Referring to the drawings, 1' designates the incoming main wire, and 2 indicates the outgoing inain wire, and with these two wires connections are made from a telephone or telephones 3 in the usual manner. phone 3 indicates a substation apparatus.

The spring-contact 11 is normally in e11- gagement with a similar spring-contact 18, extending from. a binding-post 19, and from this binding post 19 a wire 20 extends to a connection with the outgoing main-line wire 2. The circuit enters from the main wire 1 through the Wire 23,wliich connects with the binding-post 10, to which is attached a spring 11.- cuit may be secured from any one of the outlying instruments 3 over the main-line wires 1 and 2 to the central office through the springs 11 and 18.

From thetransmitter 24L a wire 25 extends to a connection with a spring contact-finger 34:, adapted to be put in connection with the eontact-finger 18 by reason of inserting the plug 29, the body portion of which is of insulatin g material. From the other bindingpost of the transmitter 24 is extended awire 36 through the primary circuit of the coil over the wire 37 to contact-finger 35, adapted to be put in connection with the contact-finger 11.

The hand-telephone is locally and permanently connected (in a local circuit containing no battery) through the secondary circuit of the coil by wires 38 and 39 and independently from the main-line wires.

1 A main battery, relay, and other apparatus ordinarily used on a call-box circuit to register the number of an outlying instrument are connected in the main-line circuit at the central office in the usual manner.

The springs 26and 27 are designed. to engage with' the metal point 28 of theplug 29 for the purpose of short-circuiting thecallbox apparatus while using the telephone.

' Then the plug 29 is inserted in the telephone-switch, the springs 11 and 18 are parted at the point and connected, respectively, with the spring-contacts 35 and 34:, thus extending Thistele- It will thus be seen that a metallic cirthe metallic circuit through the transmitter and-primary portion of the coil. Y

We will now describe our improvements and additions to the call-box mechanism.

An ordinary call box movement, which needs no description, having a frame 51, is arranged within the transmitter-box 3. To the winding-arbor is attached a support-lever 48, having a bifurcated outer end with which is to be engaged the receiver 49 in the usual manner. This lever 48 has a pin-hinge 52, designed to open one way only and to prevent any unnatural progress of the call-box movement by reason of an upward pressure at the outer end of the lever 48. The lower end of this lever 48 within the box has a lug 53, designed to engage with a pin 54 (which is securely attached to the insulating-block 56),.

in such a manner as to lift the ends of the contact-fingers 70 and 71 away from the breakwheel 56 when the support-lever 48 is moved to its extreme downward position.

Securely fixed to the frame 51 is a spring 55 with a slight pressure against the movable insulating-block 56, designed to hold it in such a position that the contact-springs 7 O and 71 will engage with the teeth on the breakwheel 56 when the same is in motion.

Stationarily fixed to the frame 51 is an insulating-block 68, to which is attached a contact-finger 69, adapted for engagement with the circuit-closer 61, which extends outward from the inner end of the lever 48.

The circuit-closingfingers 7 O and 71 are n ormally open and are adapted to be closed intermittingly by the break-wheels. From the finger a wire 72 extends to a binding-post 73, and from this binding-post 73 a groundingwire 74 is extended. The wire 72 also leads to ground contact-pieces 79 and 75. From the contact-finger 71 a wire 77 extends to a contact-piece 78, designed to disengage with the contact-piece 76 and engage with the contactpiece 75 when the button B is pressed down. From the contact-piece 76 awire 82 leads-to a connection with the incoming main wire 1. A shunt-wire 83, leading from the wire 82, is connected with a spring-finger 84, designed to be engaged by a circuit-closing finger 85, arranged nearsaid finger 84. From the frame 51 a wire 79 extends to a contact-piece 81, designed to disengage with the contact-piece 85 and engage with the contact-piece 69 when the button B is pressed down. From the contact-piece 85 a wire leads to a connection with the outgoing main wire 2. The receiver 49 is connected in an independent 10- cal circuit by itself throughthe secondary part of the coil by wires 86 and 87. From the contact-finger 69 a wire 91 extends through the primary part of the coil to one of the binding-posts of the transmitter, and from the other post of thetransmitter a wire 93 leads to a connection with the contact-finger 71.

In operation when the receiver is removed and the lever 48 is at its extreme upward position, as shown in Fig. 3, the metal circuitcloser 61 engages the contact-finger 69". In this position the primary circuit is cut in that is, the main circuit is then closed through it. This will be seen by following the circuit from the line 1 over the wire 82, contact-piece 76, spring 78, wires 77 and 93 through the transmitter and primary over the wire 91,

contact-finger 69,cirCuit-closer 61,and thence *to clear that and all other contact-fingers.

Then the wire 91 ends at the contact-closer 69, and the circuit within which the primary coil and transmitter are located is dead from the contact-finger 69 to a point where the wire 93 joins the wire 77.

e The push-buttons B and B when pressed down are used to establish the ground-circuit for carrying on conversation with the central office when the wires 1 and 2 are crossed or short circuited or when either is broken. The operation of the buttons opens either the outgoing or incoming wires at the contactpieces 76 or 78 and at the same time establishes a ground on the opposite side of the telephone from either wires 1 or 2. For instance, when the button 13 is pressed down the spring 78 engages the contact-piece 75,

and the contact-piece 75 is grounded by means side of its telephone through the ordinary district apparatus. It will also be seen that when the button B is pressed downward the wires 1 and 82 are dead or cut out, because the line ends at the contact-piece 76. Hence in the case of a cross between the wires 1 and 2 the telephone at the call-box is not cut out. The same result is obtained when the button B is pressed down, except that conversation is carried on from the ground established at the box to the one at the central office over the 'wire 1 instead of the wire 2, and wires 2 and 80 are dead or cut out.

In explaining the cooperation of the arm 61 with the contacts and 84 it may be stated that said contacts are only put into engagement upon the downward movement of the lever 48. It will be noted in the drawings that the contact 85 is somewhat longer than the contact 84, and'this lengthened end is in the are of the circle described by the arm 61. Therefore when the receiveris lifted from the lever 48 the arm 61 will engage with the contact 85 and move'it away from the contact 84. Then the receiver, however, is

placed upon the lever 48 and the lever is w moved downward, the arm 61 will engage with the extended end of the contact 85, and press it into engagement with the contact 84, thus momentarily closing the circuit to indicate to the office that the call is finished. It will be noted that the circuitclosing arm 61 will not be in engagement with either one of the contact-fingers-84 or 85 when the instrument is not in use. r

The central-office receiving and registering device and the several connections and opera- .tion may now be described. 1

, The receiving device in our system consists of two relays, one being regular and the other extra, the local points of which are connected to operate both sides of a double-pen register in the ordinary manner. The regular relay 12 is arranged to operate one pen of the register, while the extra relay 12 operates the other pen. Both relays stand open with armatures drawn away from the magnets when the line is in normal condition and not in use. As here shown, the local register-circuits are open at the contact-points of the relay-armatures. The regular relay responds to any intermittent or permanent closing of the wires 1 and 2 at any point on, the circuit. Hence if the receiver 40 at a call-boxis removedand the lever 48 is released then a movement of, the call-box will cause the wheel 56 to make,

the brush 71 contacting with the brake-wheel 56 is traced as follows: Beginning at the positive pole of the batteryA at the central office, over thewire 12 to the regular relay 12, thence over the wires 13 and 14 to binding-post 19, through contact-fingers 18 and 11 to binding-post 10, thence over wire 23,

binding-post 4, and outgoing-line wire to a point at the box where wire 1 intersects with wires 82 and S3. Thence the circuit continues over wire 82, contact-piece 76, spring 7 8, wire 77, brush 71,.thence to the brake-wheel 56, thence over wire 79, spring 81, contact piece 85, wire 80 to wire 2, thence overreturn-wire 2 to binding-post 3 of the five-point switch at the central office, thence over the left-hand lever of the switch, binding-post 5, wires 20 and 15 to the'negative pole of the battery A, thus completing the metallic circuit from any one of the outlying boxes.

The extra relay 12 responds to any intermittent or permanent ground thrown on either or both of the line-wires 1 2 at any point upon the circuit. Hence when the brush 7 O in the call-box contacts with the segments or V proj ections on the brake-wheel 56 in thesame manner as the brush 71, heretofore explained, closings will be made to cause the extra relay to be energized the same number of times as there are segments or projections on the side of the breakwvheel.

the box on the opposite edge of the registertape from that of the regular relay. This circuit is traced as follows: from the ground at the central office over wire 16 to bindingpost 6 of the five-point switch, over the righthand lever of said switch to binding-post 7, thence by wire 17 to the negative pole of the battery A, and from the opposite pole of c this battery by wire 2l to the extra relay, and then by wires 22 and 15 to the negative pole of thebattery A, and from the opposite pole of this battery by wire 12 to the regular relay, thence by wires 13 and 14, binding-post 19, contacts 18and 11, binding-post 10, wire 23, binding-post 4, over main-line wire 1 to a point where wire 1 intersects with wires 82 S3 at the call-box, thence by wire 82, cont-act.

piece 76, spring 78, wire '77, brush 71, thence across through the segment of the brake,

wheel 56 to brush 70, thence by wire 7 2, binding-post 73, and wire 74 to the ground, thus completing a metallic circuit from the central office to the call-box over line-wire 1 by using the earth as areturn-path current and 1 causing the extra relay to respond simultaneously with the regular relay. The extra- This will operate an other local circuit to record the number of relay circuit also has another path over the r incoming wire 2, which is traced as follows:

from the ground at the central office over wire 16 to binding-post 6, thence over the right-hand lever of the five-point switch ,to

binding-post 7, wire 17 to the negative pole of thebattery A, and from the opposite pole of thisbattery over wire 21 to the extra relay, thence by wires'22 and 20 to binding post 5, through left-hand lever of switch to binding-post 3, thence over the main-line wire 2 to wire 80 at the call-box, then over wire 80, contact-piece S5, spring 81, wire 79,

wheel 56, spring 70, thence by wire 72, binding-post 73, and wire 74 to the ground, thus completing a circuit from the central office to thejcall-box over line-wire 2 by using the earth as the return-path.

It will be seen that when a box is turned in I on the side of the register operated by thesame.

The dotted lines show the five-point switch at the central oflice as thrown to the left, joining wires 1 and 2 together at binding post 4 and grounding the negative end of the regular battery through the right-hand lever of the five-point switch. Calls will then be received from the outlying boxes over both wires 1 and 2, the binding-post 4., thence over wire 23, binding-post 10, springs 11 and 1S, binding-post 19, wires 14 and 13 to the regular relay 12, thence over wire 12 to the positive pole of the battery A, and from the negative pole of this battery to the ground over Wires 15 and 20, binding-post 6, and wire 16.

Our method of using the telephone in the box during wire trouble and rendering the same serviceable through the manner of effecting a ground has been heretofore explained. The parts 26 and 27 are used to cut out the relay when talking. While the plug 29 remains insertedin the switch to cut in the telephone, as shown in Fig. 2, the metal point 28 contacts with the spring-fingers 26 and 27 and serves to shunt the relay by forming a short circuit from one of the binding-posts of the regular relay over wire 30, binding-post 8, spring 27, metal point 28, spring 26, wires 31 and 13 to the other end of the regular relay.

It will be noted that this device works on an open circuit and that neither of the ground or line contact-fingers comes in contact with the break-Wheel excepting when in motion.

It will also be noted that no local batteries are used either at the instrument or central office in the operation of the telephone.

Having thus described our invention, we claim as new and desire to secure by Letters Patent 1. The combination of a signaling mechanism, comprising a call-box movement, a receiver, a supporting-lever mounted on the main arbor of said movement, a circuit-closer extended from the inner end of the lever, a contact-finger in the main line for engagement therewith, a circuit-closing switch for the main line comprising contact-fingers and adapted to be operated by the circuit-closer carried by the lever upon the downward movement of said lever, and connections comprising a grounding-switch between the main line and said circuit-closer carried by the lever, substantially as specified.

2. In a call-box system, the combination of a swinging hinge-lever for supporting a receiver, a call-box movement for moving said lever in one direction, a circuit-closer operated by said lever, circuit-closing fingers for the main line, means operated by a down- 3 Ward movement of the lever to operate said fingers and momentarily close the main line, and means comprising two switches forgroundin g main wires, a battery in the main wires for and opening the circuit should the main line become inoperative, substantially as specified.

3. In a call-box system, a call-box mechanism comprising a lever containing a hinge and adapted to support a telephone-receiver, a movable insulating-block, and supporting circuit-closers arranged in a shunt-circuit from the main line and adapted to a change of position by engagement with the support-lever when said lever is at its extreme downward movement, substantially as specified.

4. A callbox mechanism, comprising a hinged receiver-supporting lever, a circuitclosing finger carried by the said lever and having connection with the main line, a fixed finger with which such movable circuit-closing finger is designed to engage, a Wire extended from the fixed finger to a transmitter, the said wire comprising a resistance, a wire extended from the transmitter to another fixed contact-finger 71 arranged for connection with the main line, means for closing a, central-office-signaling-device circuit upon a downward movement of the hinged lever, and a local circuit comprising a resistance and receiver, said resistance being wound in close proximity to the resistance contained in the wire leading to said transmitter, substantially as specified.

5. A messenger-call system, comprising operating all the call-boxes, an ordinary callbox circuit, normally-closed contact-fingers arranged in said circuit, an auxiliary circuit 25, 36, 37, comprising a resistance and transmitter, and means for connecting said auxiliary circuit with the main-line wires, substantially as specified.

6. A messenger-call system, comprising main wires, a battery inthe main wires for operating all the call-boxes an ordinary callbox circuit containing the usual apparatus for operating the same,.normally-closed contact-fingers arranged in said circuit, an auxiliary circuit 25, 36, 37, comprising a resistance and transmitter, means for connecting said auxiliary circuit wi th the main-line wires, and a local circuit comprising a resistance and receiver, said resistance being wound in close proximity to the resistance of the auxiliary circuit, substantially as specified.

EDGAR E. SALISBURY. ALBERT E. DEAN.

Witnesses:

G. A. MOORE, F. H. MURRAY. 

